1. Field of the Invention
The present invention relates to a safety knock-type writing utensil capable of automatically changing a writing lead which has been exposed for writing into a keeping state where the writing lead is drawn, if the hook of a clip fixed in the upper portion thereof is lifted, for the purpose of sticking the writing utensil in the collar of a coat or the upper strip of a pocket, thereby preventing the leakage of ink caused due to the contact of a tip of the writing lead with on the cloth of the collar of the coat or the upper strip of the pocket and more particularly, to a safety knock-type writing utensil capable of providing a thin thickness of an outer shell and making the length of the writing lead substantially long by the change of a locking position, thereby allowing a large amount of ink to be stored into the writing lead.
2. Description of the Related Art
Well-known examples of the writing utensils are pencils, ball pen, sign pens or the like, and examples similar thereto are covering utensils for covering a correcting liquid.
Generally, the writing utensil is classified into a fixed type writing utensil which is adapted to fix a writing lead in an outer shell in the state where the writing lead is exposed at the tip thereof and cover the exposed tip of the writing lead with a cap and a knock-type writing utensil which is adapted to assemble the writing lead in the outer shell in a movable manner and expose or insert the tip of the writing lead to the outside of the outer shell or into the inside of the outer shell in accordance with the operation of a pressing member.
The conventional knock-type writing utensil is configured in such a manner that if the pressing member is pressed once, the writing lead moves to cause the tip thereof to be exposed to the outside of a cap fixed on the bottom of the outer shell and if the pressing member is re-pressed, the writing lead moves to cause the tip thereof to be drawn to the cap.
In the conventional knock-type writing utensil, also, a spring is installed to apply a force to the opposite direction of the tip of the writing lead, on the end of the lower portion of the writing lead. Further, a knocking part is installed to maintain the moving state of the writing lead, if the pressing member is pressed once and to return the writing lead to the original position, if the pressing member is re-pressed.
However, the conventional knock-type writing utensil suffers a problem that in the case where a user keeps the writing utensil in the state where the hook of a clip formed on the top portion of the outer shell is stuck in the pocket on the clothes such as suits, shirts and the like, without any insertion of the tip of the writing lead into the cap fixed on the outer shell by the re-operation of the knock part during the writing, the tip comes in contact with the cloth of the clothes, such that the clothes are contaminated or stained due to the leakage of ink from the tip of the writing lead.
To solve the problem, recently, there is proposed a safety knock-type writing utensil capable of automatically inserting the tip of the writing lead into the cap fixed in the outer shell, if the hook of the clip fixed on the top portion of the outer shell is lifted, in case of sticking the writing utensil in the collar of a coat or the upper strip of a pocket.
However, the conventionally proposed safety knock-type writing utensil should essentially insert the part components for a safety knock between the outer shell and the writing lead, such that there occur some problems that the inside diameter of the outer shell is enlarged, the appearance thereof is degraded, and the using method thereof is complicated.
In addition, the safety knock is mounted on the end portion of the hook of the clip and the part components for the safety knock are necessarily installed, such that there occur some problems that the length of the writing lead is shortened, resulting in the decrement of the amount of ink stored therein and the deterioration of the efficiency of the writing utensil itself.
Therefore, in order to compensate for the reduced amount of ink, the thickness of the writing lead should increase, but in this case, there exists a problem that a sealing material for preventing the reverse flowing of the ink at the interior of the writing lead becomes push backward due to the reduction of the surface tension by the increment of the thickness of the writing lead.
It is, therefore, an object of the present invention to provide a safety knock-type writing utensil capable of providing a safety protrusion which extrudes on a moving member fixed on the interior of an outer shell and a safety hole which is formed in a length direction of the outer shell, whereby it can provide an advantage that the length of a writing lead is enlarged, while maintaining the outer shell in a relatively thin thickness.
To attain this and other objects of the present invention, there is provided a novel safety knock-type writing utensil including: an outer shell being of a predetermined shape and having a moving groove formed in a predetermined length in a length direction thereof from the upper portion thereof; a clip assembled on the end portion of the outer shell and having a long hook in the length direction of the outer shell at the one side thereof, the hook having a locking projection extruding in the center direction of the outer shell at the end portion thereof; a writing lead inserted into the interior of the outer shell and having ink stored in the interior thereof and a tip on the end of the one side thereof where writing is conducted; an elastic member installed in the interior of the outer shell, for applying a force in an opposite direction of the tip against the writing lead; a moving member movably inserted in the top portion of the outer shell and having a predetermined length of safety protrusion inserted into the interior of the moving groove in a length direction thereof, the safety protrusion having a fixed projection extruding outwardly to be locked on the locking projection of the clip; a pressing member having a pressing protrusion inserted movably into the interior of the moving member at the part of the lower portion thereof and being contacted with the upper surface of the moving member at the outer peripheral surface of the center portion thereof; and a knock member inserted movably into the moving member, for maintaining the advanced state of the writing lead if the pressing member is pressed once in the state where the fixed projection of the moving member is locked into the locking projection of the clip, and for operating the writing lead in a backward direction by the elastic force of the elastic member if the pressing member is repressed.
The moving member comprises: a cylindrical moving body provided with one or more guide grooves and guide projections formed in turn along the inner peripheral surface thereof, each of the guide grooves forming a return preventing projection extruding in a lower height than the guide projection in a skipping manner over one guide groove; the safety protrusion extending from the one side of the moving body, formed in a predetermined length in the length direction of the outer shell, and inserted movably into the moving groove of the outer shell; and the fixed projection extruding in a predetermined length in the center direction of the outer shell, on the lower portion of the safety protrusion.
The pressing member comprises: the pressing protrusion extruding along the circumferential direction at the center portion in a length direction of the outer peripheral surface thereof and being in contact with the upper surface of the moving body of the moving member; one or more moving projections extruding at predetermined intervals on the end of the outer peripheral surface of the lower portion of the pressing protrusion, inserted movably into the guide grooves of the moving member and having a height adapted to prevent the locking to the return preventing projections; and a plurality of teeth formed on the end surface of the bottom side thereof.
The knock member comprises one or more knock projections extruding at intervals of second times the guide grooves of the moving member along the circumference on the outer peripheral surface thereof, inserted movably into the guide grooves of the moving member and having a height adapted to be locked to the return preventing projections. Each of the knock projections forms an inclined surface corresponding to the tooth of the pressing member on the upper surface thereof.
The clip comprises: a stopper assembled on the end portion of the outer shell and having a hole into which the upper side of the pressing protrusion is inserted movably, on the center portion thereof; the hook extending from the one side of the stopper and formed in a predetermined length in the length direction of the outer shell; and the locking projection protrudedly formed in the center direction of the outer shell from the lower portion of the hook, into which the fixed projection of the moving member is locked.